Fig. 2From: Electronic cleansing of tagged residue in CT colonography: what radiologists need to knowIncomplete EC due to inhomogeneously tagged faecal residue. a Faecal residues are not adequately tagged, resulting in an inhomogeneous appearance on axial 2D images (arrows). b A horizontal fluid layer is seen endoluminally before EC (arrowhead). c After EC, only sufficiently tagged parts of the residue can be subtracted, while the other parts remain in the colon lumen (arrow). d This leads to a bizarre, irregular luminal filling defect on 3D endoluminal viewsBack to article page